Remortgage Calculator — How Much Could You Save?

Strip away the jargon and remortgaging is just this: you're swapping your existing home loan for a new one, either with a different lender or the one you're already with. Most people only think about it when their fixed or tracker deal is about to expire — because the alternative is sliding onto your lender's standard variable rate, which is rarely a rate anyone would choose on purpose.

What the tool above does is take your current numbers and a new offer, then work out the bit that actually matters: not just "is the new rate lower," but whether you come out ahead once fees and any exit penalty are accounted for. A lower rate that costs £2,000 in fees isn't automatically a win — sometimes it barely breaks even.

So rather than reading rate tables and doing the maths by hand, you get a straight answer: your new monthly cost, how much you keep, and how long the fees take to pay for themselves.

Somewhere around 3 to 6 months before your current deal ends is the sweet spot. Lenders typically hold an offer open for six months, so locking one in early costs you nothing — and if a better rate shows up before completion, you can usually still switch to it.

If you've already drifted onto your lender's standard variable rate, don't wait — start now. Average SVRs through 2026 have been sitting around 6.5-7.5%, with some lenders charging above 8%, while a decent fixed deal has been closer to 4.5-5.5%. On a £200,000 mortgage that gap alone can run £250-£450 a month, which is money that adds up fast if you leave it too long.

There's also a case for switching mid-term — if your home's gone up in value, your balance has come down enough to drop into a cheaper LTV band, or rates generally have fallen by a percentage point or more. Just run the numbers first to make sure any early repayment charge doesn't wipe out the benefit.

None of this is free, which is exactly why the calculator asks for fees before it tells you the real saving. Here's roughly what to expect:

Arrangement fee — anywhere from £0 to £2,000, and it can usually be added to the loan rather than paid upfront. Valuation — most lenders don't charge for this on a remortgage. Legal work — typically £300 to £1,000, and new lenders frequently cover this as an incentive to switch.

Then there's the one that catches people out: the early repayment charge. Leave your current deal before it ends and you'll usually pay 1% to 5% of what's outstanding, with the percentage dropping by around 1% each year you stay. So a five-year fix might charge 5% if you leave in year one, down to 1% by year five. On a £200,000 balance, even a 3% charge is £6,000 — not small change.

The question worth asking isn't "will this cost me anything" — it's whether the monthly saving pays that cost back quickly enough to be worth it. That's the break-even point, and if you'll be on the new deal longer than that, switching usually stacks up. If overpaying instead makes more sense for your situation, the loan overpayment calculator is worth a look too.

Lenders don't offer the same rate to everyone — they price based on loan-to-value, which is simply your balance shown as a percentage of what your home's worth. Owe less relative to the value, and the lender's risk drops, so they reward you with a better rate.

The bands to know are 60% (the best pricing), 75%, 85%, 90% and 95% (the most expensive tier). Slip into a lower band and you could see your rate drop by roughly 0.15-0.30% — not huge on paper, but it compounds over a five-year deal. You can nudge your LTV down by overpaying, letting your property's value catch up over time, or putting down a lump sum when you remortgage. Not sure where you currently stand? The house equity calculator will show you.

Fixed rate

Your payment stays the same for 2, 3, 5 or 10 years — no surprises, easy to budget around. Makes sense if the idea of rates climbing keeps you up at night. Through 2026, 2-year and 5-year fixes have been sitting fairly close together, roughly 4.5-5.8% on average, with sharper deals available if your LTV is low.

Tracker

Moves in step with the Bank of England base rate, so your payment can go up or down. Trackers often skip the early repayment charge altogether, which suits anyone who thinks rates might fall soon, or who isn't sure how long they'll stay in the property.

Product transfer

Staying with your current lender on a new deal — fast, no solicitor, usually no fresh affordability check if your balance hasn't changed. It can complete in a matter of days, but you're only seeing that one lender's offers, which may not be the sharpest on the market. Worth comparing against a full remortgage using the switch mortgage calculator before you decide.

Say you're carrying £180,000 on a house worth £300,000 — that's 60% LTV — with 20 years still to run. Your fixed deal ended a while back, so you've drifted onto a 6.5% SVR, paying around £1,342 a month without really noticing.

A new 5-year fix comes in at 4.5%, with a £999 fee and no exit penalty since your old deal's already over. Switch, and your payment drops to roughly £1,139 a month — about £203 less every month, which adds up to £2,436 over a year.

Once the £999 fee is accounted for, you'd break even in around 5 months, and across the full five-year deal you'd come out roughly £11,200 ahead after costs. With a break-even that quick, this is about as clear-cut a "yes, switch" as you'll get. Worth running your own figures through the calculator above to see where you land.

Where these figures come from: the government-backed guidance at MoneyHelper is a solid independent read on remortgaging, the Bank of England's base rate page is what tracker deals actually follow, and the HomeOwners Alliance has a useful breakdown of typical costs. You can browse every other tool on this site from the mortgage calculators homepage.